This invention describes an approach for monolithically integrating all the
components of a photoreceiver—optical amplifier, optical band-pass filter,
and photodiode module—on a single chip. The photoreceiver array employs unique
optical amplifier and conversion technologies that provides the ultra-sensitivity
required for free space optical communications networks. As an example, by monolithically
integrating a vertical cavity surface emitting laser-diode (VCSEL) optical preamplifier
with a photodiode receiver and related amplifiers and filters on the same chip,
sensitivities as low as -47 dBm (62 photons/bit at 2.5 Gb/s), along with an order
of magnitude reduction in size, weight, and power consumption over comparable commercial-off-the-shelf
(COTS) components can be demonstrated. In accordance with another aspect of the
present invention, the concept of monolithic integration of optical amplifier with
photodetector is extended to lasers, another amplifier and modulators covering
ultra violet to very long wavelength infrared using the InP, GaAs, GaSb, InAs,
InSb, SiGe, SiC and GaN etc based technologies.